Given:
μ = 2 min, population mean
σ = 0.5 min, population standard deviation
We want to find P(x>3).
Calculate the z-score
z= (x-μ)/σ = (3-2)/0.5 = 2
From standard tables, obtain
P(x ≤ 3) = P(z ≤ 2) = 0.9772
Therefore
P(x > 3) = P(z > 2) = 1 - 0.9772 = 0.0228
Answer: 0.02275
4% simple interest after 7 years is 28% interest.
$1736 interest is 28% of $6,200
Answer:
The correct answer is t < 60.
Step-by-step explanation:
Lauren wants to keep her cell phone bill below $60 per month.
Lauren's current cellphone plan charges her a fixed price of $30 and per text price for one text is $0.50.
Let Lauren sends t texts in a complete month.
Total money spent on texts in a month is given by $ (0.50 × t)
Therefore Lauren's total spent in a month is given by $ (30 + (0.50 × t)).
But this amount should be under $60 as per as the given problem.
∴ 30 + (0.50 × t) < 60
⇒ (0.50 × t) < 30
⇒ t < 
⇒ t < 60.
So in order to keep her phone monthly bill under $60, Lauren should keep her number of texts below 60.
<span>2x^2 + 3x + 5 = 0
a = 2 b = 3 and c = 5
x = [-b +-sq root(b^2 -4ac)] / 2a
</span><span>x = [-3 +-sq root(9 -4*2*5)] / 4
x = [-3 +-sq root(9 - 40)] / 4
</span><span>x = -(3 / 4) + sq root (-36) / 4
</span><span>x = -(3 / 4) - sq root (-36) / 4
</span>